Sodic soil is one of the most common problems of limiting agricultural production that related on irrigation. Saturated hydraulic conductivity is one of hydrodynamic characteristics in evaluating transmission flow through underground levels. To investigate the role of increment of exchangeable sodium in hydraulic conductivity changes (as characterized by the mobility of water in soil) an experi...

1 Spatial distributions of tropical trees often correlate with environmental variation, suggesting that ecological sorting caused by niche differentiation may be important for maintaining species diversity. 2 Four soil types have been identified in a 52-ha forest dynamics plot in Bornean mixed dipterocarp forest (ranked by increasing fertility and moisture: sandy loam, loam, fine loam, and clay...

Machinery for sowing wheat directly into rice residues has become more common in the rice-wheat systems of the north-west Indo-Gangetic Plains of South Asia, with increasing numbers of farmers now potentially able to access the benefits of residue retention. However, surface residue retention affects soil water and temperature dynamics, thus the optimum sowing date and irrigation management for...

Turfgrass évapotranspiration. R. Tovey, J. S. Spencer and D. C. • Muckel. 1969. Agronomy Journal. 61:863-867. (from the University of Nevada, Reno, Ne v. 89507). The lysimeter technique was utilized to measure the rate of évapotranspi ra t ion from two types of turf grown on two different soil textures. The two types of turfgrass were (a) a cool season turf composed primarily of Kentucky bluegr...

the prevalent method of irrigation in paddy fields in iran is continuous ponding, which changes to intermittent method at the time of water shortage. soil cracks are the main problem in intermittent irrigation. in this study, effects of adding rice straw on some soil physical characteristics and cracks were studied in paddy soils of the guilan province of iran. the experiment was performed as s...

Many arable lands have accumulated large reserves of residual phosphorus (P) and a relatively large proportion of soil P is less available for uptake by plants. Root released organic anions are widely documented as a key physiological strategy to enhance P availability, while limited information has been generated on the contribution of rhizosphere organic anions to P utilization by crops grown...